Angioplasty and ablative devices having onboard ultrasound components and devices and methods for utilizing ultrasound to treat or prevent vasopasm

ABSTRACT

A catheter device incorporating combined ultrasound ablation and balloon dilation components. The catheter device generally comprises an elongate catheter body having proximal and distal ends and an outer surface. Disposed on the outer surface of the catheter body is a dilation balloon. At least one balloon inflation lumen fluidly connects the proximal end of the catheter body to the dilation balloon to permit injection of inflation fluid into the dilation balloon. Extending longitudinally through the catheter body is an ultrasound transmission member having a proximal end and a distal end, with the proximal end being connectable to an ultrasound transducer such that ultrasonic energy will pass through the ultrasound transmission member to the distal end thereof. In alternative embodiments of the present invention, there are provided catheter devices incorporating combined ultrasound ablation and laser ablation components as well as combined ultrasound ablation and atherectomy ablation components.

RELATED APPLICATION

This patent application is a continuation-in-part of U.S. patentapplication Ser. No. 640,190 filed Jan. 1, 1991 entitled ULTRASOUNDANGIOPLASTY DEVICE INCORPORATING IMPROVED TRANSMISSION MEMBER ANDABLATION PROBE, and U.S. patent application Ser. No. 878,795 filed May5, 1992 entitled MODIFIED ULTRASONIC CATHETER U.S. Pat. No. 5,267,954,the entire disclosures of both such prior patent applications beinghereby expressly incorporated herein by reference.

FIELD OF THE INVENTION

The present invention relates generally to medical devices and moreparticularly to devices and methodology for treating occlusive vasculardisorders and for preventing untoward side effects associated with suchtreatment.

BACKGROUND OF THE INVENTION

A number of devices have heretofore been utilized for removal, dilationor ablation of occlusive matter from the lumens of blood vessels.

Examples of the types of devices which have heretofore been utilized todilate, ablate or otherwise remove obstructions from blood vesselsinclude a.) balloon angioplasty catheters which function to radiallydilate an occlusive lesion, b.) ultrasound ablation catheters whichserve to ultrasonically ablate the occlusive lesion, c.) laser catheterswhich vaporize or ablate the occlusive lesion by laser energy and d.)atherectomy devices which operate to cut, shave, or grind occlusivematter from the blood vesel lumen using mechanical means.

Examples of ultrasonic ablation devices are described in U.S. Pat. Nos.3,433,226 (Boyd), 3,823,717 (Pohlman, et al.), 4,808,153 (Parisi),4,936,281 (Stasz), 3,565,062 (Kuris), 4,924,863 (Sterzer), 4,B70,953(Don Michael, et al.), 5,069,664 (Suess, et al.) and 4,920,954 (Alliger,et al.), as well as other patent publications W087-05739 (Cooper),W089-06515 (Bernstein, et al.), W090-0130 (Sonic Needle Corp.), EP316789(Don Michael, et al.), DE 3,821,836 (Schubert), DE2438648 (Pohlman), andEP 0443256A1 (Baruch).

Examples of atherectomy devices include those described in U.S. Pat. No.5,100,423 (Fearnot) and EP0347098A2 (Shiber).

Although laser ablation, ultrasonic ablation and atherectomy deviceshave been utilized for ablating or removing occlusive matter from bloodvessels, balloon dilation angioplasty remains the most widely utilizedinterventional technique for nonsurgical restoration of patency inoccluded or partially occluded blood vessels. One problem associatedwith balloon dilation angioplasty is that, in blood vessels which arefully occluded, it is sometimes difficult to penetrate the occlusivematter in a manner which permits the dilation balloon to becomeoperatively positioned adjacent the occlusive lesion. In view of thisproblem, there exists a need in the art for development of a balloondilation catheter having an onboard ablation component for partiallyablating, or opening a channel through the offending lesion, therebyfacilitating operative advancement and positioning of the dilationballoon within the offending lesion.

Another problem associated with balloon dilation angioplasty as well asother intravascular ablation or surgical procedures (e.g. laser ablationor atherectomy) is the occurrence of constrictive vasospasm in theaffected blood vessel during or immediately after the procedure. Severevasospasm may result in complete occlusion of the affected blood vessel,thereby presenting an acute clinical emergency.

The occurrence of vasospasm can result in ischemia or infarction and, atlast theoretically, may promote intravascular thrombus formation. See,Fischell, T. A., Derby, G., Tse, T. M. and Stadius, M. L.; CoronaryArtery Vasoconstriction Routinely Occurs After Percutaneous TransluminalCoronary Angioplasty: A Quantitative Arteriographic Analysis;Circulation; Vol 78; 1323-1334 (1988). One means of treating vasospasmis to administer vasorelaxant pharmacologic agents to prevent or relievethe untoward vasospasm. Recent observations have indicated that theadministration of ultrasonic energy to the blood vessel, in the regionof the vasospasm, may effect rapid vasorelaxation without the need foradministration of pharmacological agents. (Abstract) Chokahi, S. K. , etal. ULTRASONIC ENERGY PRODUCES ENDOTHELIUM-DEPENDENT VASOMOTORRELAXATION IN VITRO, Abstracts of the 62nd Scientific Sessions of theAmerican Heart Association (1989). Accordingly, it is desirable todevelop ultrasonic devices and methods for preventing or treatingvasospasm angioplasty or ablative procedures.

SUMMARY OF THE INVENTION

The present invention includes a combination balloon dilation/ultrasoundablation catheter device. The combination balloon dilation/ultrasoundablation device of the present invention comprises an elongateintravascular catheter having at least one dilation balloon formedthereon for radially or otherwise dilating an occlusive lesion.Additionally, an elongate ultrasound transmission member or waveguideextends longitudinally through the body of the catheter. The proximalend of the ultrasound transmission member or waveguide is connectable toan ultrasound generating device, such as an ultrasound transducer. Thedistal end of the ultrasound transmission member or waveguide ispositioned adjacent, flush with, or near the distal end of the catheterbody and may be securely attached or anchored thereto. When it isdesired to advance the distal end of the catheter body into a body ofocclusive material or high grade stenosis, the ultrasound transmittingdevice may be operated to pass ultrasonic energy through the ultrasoundtransmission member or waveguide at a wavelength and power sufficient toeffect ultrasonic ablation of at least a portion of the occlusivematter, so as to form a pilot hole or passageway therethrough.Thereafter, the catheter may be further advanced distally to a pointwhere the dilation balloon is positioned within or adjacent theremainder of the obstructive matter. The dilation balloon may then beoperated in accordance with standard balloon dilation angioplastyprinciples to effect radial or other dilation of the occlusive matter.Additionally, the presence of the ultrasound component within theultrasound ablation/balloon dilation catheter device provides a meansfor delivering ultrasound energy to prevent or treat vasospasm.

Additionally, the present invention includes methods and devices forpreventing or treating vasospasm in tubular anatomical structures suchas blood vessels during various intravascular, diagnostic orinterventional procedures. Ultrasonic energy at a wavelength ofapproximately 20 Khz is preferable for preventing or treating vasospasm.The ultrasound for preventing or treating vasospasm may be deliveredthrough an onboard ultrasound transmission component positioned within astandard diagnostic or interventional catheter such as a balloondilation angioplasty catheter, laser ablation catheter or atherectomycatheter device. Alternatively, if such devices are devoid of an onboardultrasound transmitting component, a separate ultrasound transmissionwire or waveguide may be rapidly inserted through the working lumen orguidewire lumen of a standard catheter or other intravascular device soas to prevent or treat vasospasm by delivery of ultrasonic energy at ornear the distal end of the catheter or device.

Further and more specific aspects of the present invention Will becomeapparent to those skilled in the art upon reading and understanding thefollowing detailed description of preferred embodiments, and theaccompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

These as well as features of the present invention will become moreapparent upon reference to the drawings wherein:

FIG. 1 is a perspective view of a catheter device of a first embodimentof the present invention incorporating both ultrasound ablation andballoon dilation components;

FIG. 2 is an enlarged perspective view of a proximal end connectorassembly positionable on the proximal end of the ultrasound/ballooncatheter body shown in FIG. 1;

FIG. 3 is an enlarged perspective view of the distal end of theultrasound/balloon catheter body designated by the numeral 3 in FIG. 1;

FIG. 4 is a cross-sectional view taken along line 4--4 of FIG. 3;

FIG. 4a is an enlarged cross-sectional view of the distal end of theultrasound/balloon catheter body designated by the numeral 4a in FIG. 4;

FIG. 5 is a cross-sectional view taken along line 5--5 of FIG. 2;

FIG. 6 is a cross-sectional view taken along line 6--6 of FIG. 2;

FIG. 7 is a perspective view of a laser ablation catheter equipped withan ultrasound component for delivering vasorelaxant ultrasound energyduring a laser ablation procedure;

FIG. 8 is an enlarged perspective view of the distal portion of thelaser catheter body designated by the numeral 8 in FIG. 7;

FIG. 9 is a cross-sectional view taken along line 9--9 of FIG. 8;

FIG. 10 is a cross-sectional view taken along line 10--10 of FIG. 7;

FIG. 11 is a perspective view of an insertable ultrasound device whichis insertable through a working lumen of a catheter to effect ultrasonictreatment of vasospasm;

FIG. 12 is a perspective view of a conventional proximal end connectorassembly for use with the insertable ultrasonic device shown in FIG. 11;

FIG. 13 is a perspective view of an atherectomy catheter device equippedwith an ultrasound component for delivering vasorelaxant ultrasoundenergy during an atherectomy procedure;

FIG. 14 is an enlarged perspective view of the distal portion of thecatheter body designated by the numeral 14 in FIG. 13.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The detailed description set forth below in connection with the appendeddrawings is intended merely as a description of the presently preferredembodiments of the invention, and is not intended to represent the onlyform in which the present invention may be constructed or utilized. Thedescription sets forth the functions and sequence of steps forconstruction and implementation of the invention in connection with theillustrated embodiments. It is to be understood, however, that the sameor equivalent functions and sequences may be accomplished by differentembodiments that are also intended to be encompassed within the spiritand scope of the invention.

i. A Preferred Ultrasound Ablation/Balloon Dilaton Catheter

FIG. 1 is a perspective showing of an ultrasonic ablation/balloondilation catheter device 10 constructed in accordance with a firstembodiment of :he present invention which incorporates combinedultrasound ablation and balloon dilation components. In the firstembodiment, the catheter device 10 comprises an elongate catheter body12 having a proximal end 14, a distal end 16 and defining an outersurface 18. Mounted on the proximal end 14 of the catheter body 12 is aproximal end connector assembly 20. An ultrasound transducer 22 isconnected to the proximal end of the connector assembly 20. Anultrasound generator 24 having a foot actuated on/off switch 26 isoperatively connected to the ultrasound transducer 22 so as to sendultrasonic energy through the catheter body 12 via an ultrasoundtransmission member 28 or waveguide Which extends longitudinally throughthe catheter body 12. The ultrasound transmission member 28 or waveguidehas a proximal end which is connectable to the ultrasound transducer 22such that the ultrasonic energy will pass through the ultrasoundtransmission member 28 to the distal end 30 thereof and, hence, thedistal end 16 of the catheter body 12.

In the first embodiment, the ultrasound transmission member 28 may beformed of any material capable of effectively transmitting theultrasonic energy from the ultrasound transducer 22 to the distal end 16of the catheter body 12, including but not necessarily limited to metal,plastic, hard rubber, ceramic, and/or composites thereof. In accordancewith one aspect of the invention, all or a portion of the ultrasoundtransmission member 28 may be formed of one or more materials whichexhibit super-elasticity. Such materials should preferably exhibitsuper-elasticity consistently within the range of temperatures normallyencountered by the ultrasound transmission member 28 during operation ofthe catheter device 10. Specifically, all or part of the ultrasoundtransmission member 28 may be formed of one or more metal alloys knownas "shape memory alloys".

Examples of super-elastic metal alloys which are usable to form theultrasound transmission member 28 of the present invention are describedin detail in U.S. Pat. Nos. 4,665,906 (Jervis); 4,565,589 (Harrison);4,505,767 (Quin); and 4,337,090 (Harrison). The disclosures of U.S. Pat.Nos. 4,665,906; 4,565,589; 4,505,767; and 4,337,090 are expresslyincorporated herein by reference insofar as they describe thecompositions, properties, chemistries, and behavior of specific metalalloys which are super-elastic within the temperature range at which theultrasound transmission member 28 of the present invention operates, anyand all of which super-elastic metal alloys may be usable to form thesuper-elastic ultrasound transmission member 28.

In particular, one presently preferred super-elastic metal alloy ofwhich the ultrasound transmission member 28 may be formed is anickel-titanium alloy wire made up of 55.8 weight percent nickel (NiTicontaining 55.8% weight % Ni balance Ti). Such material is commerciallyavailable as Tinel™ Wire from Raychem Corporation, Menlo Park, Calif. Aswill be recognized, in any embodiment of the present invention, theultrasound transmission member 28 may be tapered, narrowed, or otherwisereduced in cross-sectional dimension within the catheter device 10 so asto decrease the rigidity of the ultrasound transmission member 28 and/orto cause amplification of the ultrasound transmitted to and from thedistal end 30 thereof.

Referring now to FIGS. 2 and 5, the proximal end connector assembly 20comprises an elongate, rigid body 32 having a hollow bore 34 extendinglongitudinally therethrough. In the embodiment shown, the elongate body32 of the proximal end connector assembly 20 is actually constructed ofa frontal portion 36, a mid-portion 38 and a rear portion 40. Thefrontal portion 36 of the elongate body 32 is firmly connected to theproximal end 14 of the catheter body 12 by way of a threaded grippingmember 42 engaged thereto. As will hereinafter be more fully described,the proximal end 14 of the catheter body 12 has a flared configurationand includes an annular flange formed on the outermost end thereof whichis brought into sealed engagement with the connector assembly 20 whenthe gripping member 42 is threadably engaged to the body 32. Theproximal end of the frontal portion 36 is connected to the distal end ofthe mid-portion 38 of the elongate body 32 by way of a second grippingmember 44. As will be recognized, to facilitate the aforementionedconstruction, threads are formed on the opposite ends of the frontalportion 36 of the elongate body 32. Threads are also formed on theproximal end of the mid-portion 38 of the elongate body 32 such that themid-portion 38 may be threadably received into a correspondinglythreaded bore formed in the distal end of the rear portion 40 of theelongate body 32.

Referring now to FIG. 6, the ultrasound transmission member 28 orwaveguide extends longitudinally through the entire catheter body 12 andthrough the proximal end connector assembly 20. The ultrasoundtransmission member 28 is inserted into and engaged by a threadedproximal connector 46. Threaded proximal connector 46 is positionedwithin a cylindrical recess 48 formed in the proximal end of theconnector assembly 20. The ultrasound transducer 22 may be screwed ontoand threadably connected to the proximal connector 46 to accomplishpassage of ultrasonic energy through the ultrasound transmission member28 in a distal direction to the distal end 16 of the catheter body 12.

The extreme proximal end of the connector assembly 20 is provided with asonic connector assembly or apparatus configured to effect operativeattachment of the proximal end of the ultrasound transmission member 28to the horn of the ultrasound transducer 22. The sonic connectorassembly or apparatus is preferably configured and constructed to permitpassage of ultrasound energy through the ultrasound transmission member28 with minimal lateral side-to-side movement of the ultrasoundtransmission member 28 while, at the same time, permitting unrestrictedlongitudinal forward/backward vibration or movement of the ultrasoundtransmission member 28. Specifically, a distal portion of the body ofthe threaded proximal connector 46 is configured to receive therein acompressible gripping ferrule 50. Compressible gripping ferrule 50 has asmall central aperture formed therethrough through which the ultrasoundtransmission member 28 passes, as shown. A frontal member 52 isthreadably tightened within the frontal portion of the body of theproximal connector 46 so as to compress gripping ferrule 50, therebycausing gripping ferrule 50 to firmly grip and hold the ultrasoundtransmission member 28 in place within the body of the proximalconnector 46. The proximal connector 46 may then be compressed orcrimped inwardly so as to be additionally crimp connected or crimp fitto the proximal end of the ultrasound transmission member 28, therebyproviding further gripping and attachment of the sonic connectorassembly to the proximal end of the ultrasound transmission member 28. Aseries of threads are formed on the outer surface of the proximalconnector 46 to permit the distal end of the ultrasound transducer hornto be threadably screwed onto and releasably attached to the sonicconnector assembly. Thus, the frontal member 52, gripping ferrule 50,and proximal connector 46 combine to form a sonic connector assembly towhich the horn of the ultrasound transducer 22 may be attached andthrough which the ultrasonic energy may be transmitted into theultrasound transmission member 28. A lumen 54 extending through the rearportion 40 of the connector assembly 20 is specifically sized to belarge enough to permit the ultrasound transmission member 28 to passtherethrough with a small amount of space remaining between the outersurface of the ultrasound transmission member 28 an the inner luminalsurface of the lumen 54.

Referring now to FIG. 5, in the first embodiment the catheter body 12 isformed of two concentric single lumen tubes. Particularly, the catheterbody 12 comprises a first outer tube 56 which defines the outer surface18 of the catheter body 12 and further defines a first inner luminalsurface 58. Longitudinally disposed through and within the lumen of thefirst outer tube 56 is a second inner tube 60 defining a second outersurface 62 and a second inner luminal surface 64. As seen in FIG. 5, thepreviously described annular flange formed about the proximal end 14 ofthe catheter body 12 is actually formed about the proximal end of theouter tube 56 and engaged to the connector assembly 12 via the grippingmember 42. In the first embodiment, outer tube 56 and inner tube 60 arepreferably sized such that when the inner tube 60 is longitudinallydisposed within the outer tube 56, space 66 is defined between thesecond outer surface 62 of the inner tube 60 and the first inner luminalsurface 58 of the outer tube 56.

Attached to a portion of the first inner luminal surface 58 adjacent theproximal end of the outer tube 56 is a wall member 68 which extendstoward the proximal end of the connector assembly 20. Wall member 68 ispreferably attached to the first inner luminal surface 58 via a heatsealing process, though an adhesive or other attachment method may beutilized as an alternative. As further seen in FIG. 5, the proximal edof the inner tube 60 is formed in a manner wherein a proximal portionthereof extends toward the proximal end of the connector assembly 20.Advantageously, when the proximal end of the inner tube 60 is engaged tothe gripping member 42, the portion thereof extending toward theproximal end of the connector assembly is interfaced to the wall member68 in a manner forming a balloon inflation lumen 70 which is in fluidcommunication with the space 66 defined between the inner tube 60 andouter tube 56. In this respect, the proximal end of the inner tube 60 isengaged to the connector assembly 20 in a manner wherein the only accessinto the space 66 is via the balloon inflation lumen 70. In the firstembodiment, the space 66 comprises part of the balloon inflation lumen70 due to its fluid communication therewith. It will be recognized thatas an alternative to forming the balloon inflation lumen 70 from thewall member 68 and a portion of the inner tube 60, such lumen may beformed from a separate tubular member which is fluidly connected to theproximal end of the inner tube 60 in a manner wherein the space 66 isaccessible only thereby. The use of the balloon inflation lumen 70 inconjunction with the space 66 will hereinafter be discussed.

Formed on and extending outwardly from the body 32 in the mid-portion 38of the connector assembly 20 is a first fluid inlet sidearm orirrigation port 72. Extending through the irrigation port 72 is a hollowbore which is in fluid communication with the bore 34 of the connectorassembly 20. Threadably engaged to the outermost end of the irrigationport 72 is a connector member 74 which is used to threadably connect theirrigation port 72 to an irrigation fluid supply source 76. Also formedon the body 32 and extending outwardly from the mid-portion 38 of theconnector assembly 20 is a balloon inflation port 78. Like theirrigation port 72, balloon inflation port 78 includes a hollow borewhich extends therethrough and is in fluid communication with theballoon inflation lumen 70 and, hence, the space 66. Attached to theoutermost end of balloon inflation port 78 is a connector member 80which is used to threadably engage the balloon inflation port 78 to aballoon inflation fluid supply source 82.

As best seen in FIG. 5, the ultrasound transmission member 28 extendsthrough the bore 34 of the connector assembly 20 and is subsequentlyreceived into the lumen of the inner tube 60. Due to the fluidcommunication between the irrigation port 72 and the bore 34,pressurized fluid such as a coolant liquid may be infused throughirrigation port 72, bore 34, and through the lumen of the inner tube 60.Such liquid will flow out the distal end 16 of the catheter body 12 in amanner which will hereinafter be described. The temperature and flowrate of such coolant liquid may be specifically controlled to maintainthe temperature of the ultrasound transmission member 28 at a desiredtemperature within its optimal Working range. In particular, inembodiments of the invention wherein the ultrasound transmission member28 is formed of a metal alloy which exhibits optimal physical properties(e.g. super elasticity) within a specific range of temperatures, thetemperature and flow rate of coolant liquid infused through theirrigation port 72 may be specifically controlled to maintain thetemperature of the ultrasound transmission member 28 within the range oftemperatures at which it demonstrates its most desirable physicalproperties. For example, in embodiments of the invention wherein theultrasound transmission member 28 is formed of a shape memory alloywhich exhibits super elasticity when in its martensite state, but whichloses super elasticity as it transitions to an austenite state, it willbe desirable to adjust the temperature and flow rate of the coolantinfused through the irrigation port 72 so as to maintain the shapememory alloy of the ultrasound transmission member 28 within atemperature range at which the alloy will remain in its martensite stateand will not transition to an austenite state. The temperature at whichsuch shape memory alloys transition from a martensite state to anaustenite state is known as the "martensite transition temperature" (Ms)of the material. Thus, in these embodiments, the fluid infused throughirrigation port 72 will be at such temperature, and will be infused atsuch rate, as to maintain the shape memory alloy of the ultrasoundtransmission member 28 below its martensite transition temperature (Ms).

Formed on the body 32 and extending outwardly from the frontal portion36 of the connector assembly 20 is a guidewire insertion sidearm 84 forreceiving a transluminal body guidewire 86. The guidewire insertion arm84 includes a hollow bore extending therethrough which communicates withthe bore 34 of the connector assembly 20. A guidewire gripping/sealingapparatus 88 may be mounted on guidewire insertion arm 84 to grasp andhold the guidewire 86 in fixed longitudinal position relative to thecatheter device 10 and to provide a seal to prevent backflow of bloodthrough the catheter device 10. Examples of guidewire gripping/sealingapparatus 88 which may be utilized in this application include thosewhich are available commercially as Product Nos. 1905017A and 1905014Afrom Medical Disposables International, West Conshocken, Pa.

In the embodiment of the connector assembly 20 shown in FIG. 5, anangled guidewire diverter tube 90 is positioned within the bore 85 ofguidewire insertion arm 84 and a portion of the longitudinal bore 34 ofthe body 32 of the connector assembly 20. Additionally, the distal endof the diverter tube 90 extends through the bore 34 and into theproximal end of the inner tube 60. The guidewire diverter tube 90comprises an obtuse angular bend B having an aperture 92 formed at theouter apex of such angular bend B. The aperture 92 is sufficiently largeto permit the ultrasound transmission member 28 to pass longitudinallytherethrough without damping or interference from the body of thediverter tube 90. Also, the aperture 92 is sufficiently large to allowirrigation/coolant liquid to flow from the bore 34 therethrough when theultrasound transmission member 28 is positioned within the aperture 92.As will hereinafter be discussed, the guidewire 86 is inserted into thedistal end 16 of the catheter body 12 and into the lumen of the innertube 60. As such, the diverter tube 90 is configured and constructedsuch that, as the proximal end of the guidewire 86 is advanced in aproximal direction through the lumen of the inner tube 60, it willimpinge against the wall of the diverter tube 90 and will thus bediverted outwardly through the guidewire insertion arm 84.

Referring now to FIGS. 3, 4, and 4a, as previously specified, thecatheter body 12 of the catheter device 10 comprises the outer tube 56having the inner tube 60 disposed longitudinally therein. The guidewire86 extends longitudinally through the lumen of the inner tube 60 as doesthe ultrasound transmission member 28. In the first embodiment, thecatheter body 12, and more particularly the outer tube 56, has anoutside diameter of 0.5 mm-5.0 mm. However, if the catheter body 12 isintended for insertion into tortuous or relatively small anatomicalstructures (e.g., the coronary arteries), it is preferable that theouter diameter of the outer tube 56 be 0.25 mm-2.5 mm.

As seen in FIG. 4, the inner tube 60 is sized to extend axially beyondthe distal end of the outer tube 56 and is formed to include an enlargedannular head portion 94 about the distal end thereof. Additionally,formed about the distal end of the outer tube 56 is an annular recessedportion 96. Attached to the distal end 16 of the catheter body 12 is adilation balloon 98 having a proximal end attached to the outer tube 56by an overlapping joint (OJ) and a distal end of attached to the innertube 60. Particularly, the proximal end of the dilation balloon 98 isnested into the annular recessed portion 96 and sealed thereagainst withthe proximal end being abutted against the head portion 94 and sealedagainst a portion of the outer surface 62 of the inner tube 60.Advantageously, due to the configuration of the head portion 94 andrecessed portion 96, the proximal end of the balloon 98 forms acontinuous surface with the outer tube 56 when sealed thereto with thedistal end forming a continuous surface with the head portion 94 of theinner tube 60 when sealed to the outer surface 62 of the inner tube 60.The balloon 98 is preferrably sealed to the outer tube 56 at overlappingjoint (OJ) and to the distal portion of inner tube 60 by a heat sealingprocess, though adhesives or other suitable affixation apparatus,substances or methods may also be utilized.

As shown in FIG. 4, the distal most portion of inner tube 60 is enlargedor outwardly tapered such that the distal end of inner tube 60 is ofgreater diameter than that portion of inner tube 60 which residesadjacent the overlapping joint (OJ) between outer tube 56 and balloonmember 98. Such tapering of the inner tube 60 prevents or minimizesinterference with or contact between the inner tube 60 and the recessedportion 96 of outer tube 56 at overlapping junction (OJ). Additionally,such minimization of the diameter of a portion of the inner tube 60further enables the deflated balloon 98 to assume a substantially flatnon-prodrudding configuration consistent with the remainder of the outersurface of the catheter body 12. In this regard, the balloon member 98may be specifically shaped such that its diameter tapers inwardly ornarrows from its proximal end to its distal end in porportion to thecorresponding widening or enlargement of the inner tube 60, therebyensuring a completely flat non-protrudding configuration when theballoon member 98 is deflated and collapsed against the outer surface ofinner tube 60.

As also seen in FIG. 4, when the dilation balloon 98 is attached to theouter tube 56 and inner tube 60 in the aforementioned manner, aninflation space 100 is defined between the dilation balloon 98 and outersurface 62 of the inner tube 60. In the first embodiment, the inflationspace 100 is placed in fluid communication with the space 66 via anannular passage 102 defined by the recessed portion 96 of the outer tube56. As previously specified, the space 66 is in fluid communication withand forms part of the balloon inflation lumen 70 which is itself fluidlyconnected to the inflation fluid supply source 82 via the inflation port78. As such, the balloon inflation fluid introduced into the inflationport 78 flows through the inflation lumen 70, space 66, and annularpassage 102 into the inflation space 100 in a manner operable toselectively dilate or deflate the balloon 98. In the first embodiment,the dilation balloon 98 is approximately 5 millimeters in length and ispositioned on the catheter body 12 such that the distal-most extent ofthe dilation balloon 98 is approximately 3 millimeters from the distalend 16 of the catheter body 12, and more particularly, the distal-mostextent of the head portion 94 of the inner tube 60.

As best seen FIG. 4a, the distal end 30 of the ultrasound transmissionmember 28 has an enlarged configuration. Mounted on the enlarged distalend 30 of the ultrasound transmission member 28 is a distal head 104. Inthe embodiment shown, the distal head 104 comprises a generally round,conical, or disk-shaped distal portion 106 and a reduced diameter neckor proximal portion 108. The outer diameter of the proximal portion 108of the distal head 104 is approximately the same as or slightly lessthan the inner diameter of the lumen of the inner tube 60 such that theproximal portion 108 of the distal head 104 may be inserted into thedistal end of the lumen of the inner tube 60 to a point where thedistal-most end of the head portion 94 abuts against the proximal aspectof the distal portion 106 of the distal head 104, as shown. The distalhead 104 is firmly bonded, attached, or connected to the catheter body12, and more particularly the inner tube 60, such that the distal head104 is prevented from undergoing longitudinal or transverse movementsseparate from or relative to the catheter body 12. Such non-movableaffixation of the distal head 104 to the inner tube 60 preventslongitudinal or transverse movement of the distal head 104 apart fromthe catheter body 12. Additionally, such affixation of the distal head104 to the inner tube 60 increases the conveyance of ultrasound energyinto the distal end 16 of the catheter body 12, thereby resulting inenhanced cavitation effects created by the distal end 16 of the catheterbody 12. Such bonding connection or attachment of the distal head 104 tothe inner tube 60 of the catheter body 12 may be accomplished by anysuitable means. One means of attaching the distal head 104 to the innertube 60 is through the use of an adhesive which is applied to theproximal portion 108 of the distal head 104 prior to insertion thereofinto the distal end of the inner tube 60. The adhesive may comprise anysuitable adhesive, such as cyanoacrylate (e.g., Loctite™, Loctite Corp.,Ontario, Canada or Aron Alpha™, Borden, Inc., Columbus, Ohio) orpolyurethane (e.g., Dymax™, Dymax Engineering Adhesive, Torrington,Conn.) to firmly bond and attach the distal head 104 to the inner tube60. The distal head 104 may be formed of any suitable rigid material,such as metal or plastic. In devices wherein the distal head 104 isformed of plastic, the surrounding inner tube 60 may be thoroughlywelded, heat sealed, or solvent welded to the plastic distal head 104,in accordance with the types of plastics employed.

In the alternative to the use of adhesives, various mechanical orfrictional connectors, such as screw threads, lugs, or other surfacemodifications formed on the proximal portion 108 of the distal head 104,may be utilized to hold the distal head 104 in a fixed position relativeto the inner tube 60 of the catheter body 12. In such embodiments,corresponding grooves, detents, or surface modifications may also beformed in the surrounding inner luminal surface 64 of the inner tube 60so as to cooperate with any such threads, lugs, or other surfacemodifications formed on the opposing surface of the distal head 104.Such threads, lugs, or other surface modifications will be configuredand constructed as to mechanically or frictionally hold the distal head104 in fixed position relative to the catheter body 12.

The distal head 104 is preferably formed of radiodense material so as tobe easily discernible by radiographic means. Accordingly, the distalhead 104 may preferably be formed of metal or, alternatively, may beformed of plastic, ceramic, or rubber materials, optionally having oneor more radiodense markers affixed thereto or formed therein. Forexample, the distal head 104 may be molded of plastic, such asacrylonitrile-butadiene-styrene (ABS) and one or more metallic foilstrips or other radiopaque markers may be affixed to such plastic distalhead 104 in order to impart sufficient radiodensity to permit the distalhead 104 to be readily located by radiographic means. Additionally, inembodiments wherein the distal 104 is formed of molded plastic or othernon-metallic material, a quantity of radiodense fillers, such aspowdered Bismuth or Barium Sulfate (BaSo), may be disposed within theplastic or other non-metallic material of which the distal head 104 isformed so as to impart enhanced radiodensity thereto.

Extending longitudinally through the distal head 104 is a guidewirepassage aperture 110. The guidewire passage aperture 110 is preferablyformed through the distal head 104 at a location wherein the guidewire86 may pass therethrough into the lumen of the inner tube 60. Theguidewire passage aperture 110 may be sized so as to be slightly largerthan the outer diameter of the guidewire 86 to be passed therethrough soas to permit fluid to be infused through the lumen of the inner tube 60and pass out of the guidewire passage aperture 110, even when theguidewire 86 is extending therethrough. The distal head 104 furtherincludes a conical depression 112 disposed in the proximal portion 108thereof to direct the guidewire 86 into the guidewire passage aperture110.

As an alternative to the utilization of the distal head 104, the distalend 30 of the ultrasound transmission member 28 may be directly affixedto the distal end of the catheter body 12, and more particularly to adistal portion of the inner luminal surface 64 of the inner tube 60.Additionally, the distal head 104 mounted to the distal end 30 of theultrasound transmission member 28 may be unaffixed to the inner tube 60of the catheter body 12.

The combination ultrasound ablation/balloon dilation catheter device 10of the present invention is particularly suited for treating totalocclusions and high grade stenoses of blood vessels, wherein it isdifficult to initially advance the dilation balloon 98 due to the degreeof vessel occlusion. In such cases, the ultrasound ablation component ofthe device may be utilized to form a pilot hole or passageway throughthe occlusion or high grade stenosis, thereby enabling the distalportion of the catheter 12 to be advanced into the occlusion or stenosissuch that the deflated balloon 98 will be operatively positionedadjacent thereto. Thereafter, the balloon 98 may be repeatedly inflatedand deflated, in accordance With standard balloon dilation angioplastytechniques, to effect dilation of the remainder of the occlusion orstenosis.

If vasoconstriction or vascular spasm occurs before, during or after theballoon dilation by balloon 98, the ultrasound component of the device10 may be utilized to treat or reverse such vasoconstriction or spasm.This is accomplished by utilizing the signal generation device 24 andultrasound transducer 22 to cause ultrasonic energy at approximately 20Khz frequency to pass through the ultrasound transmission member 28,thereby causing corresponding ultrasonic vibration of the distal head104. With the balloon 98 deflated, the operator may elect to move thecatheter 12 back and forth slightly to cause the distal head 104 totraverse the entire region of the vasospasm. In other cases, it may bedesirable to allow the catheter 12 to remain in a substantially fixedlongitudinal position while emitting the vasospasm-treating ultrasoundfrom the distal head 104 of the device 10.

Liquid may be infused through the lumen of the inner tube 60 via theirrigation port I2 to provide a continuous liquid environment around thedistal head 104 during the ultrasound vasorelaxation treatment. Also, ifnecessary, pharmacologic agents may be infused through the lumen of theinner tube 60 via the irrigation port 72.

Thus, as described hereabove, the combination ultrasoundablation/balloon dilation catheter device 10 of the present inventionprovides enhanced capabilities for ablating and dilating severeocclusions or high grade stenoses. Additionally, unlike other balloondilation catheters of the prior art, the device 10 of the presentinvention offers the capability of delivering ultrasound treatment toprevent or reverse vasospasm before, during or immediately after thedilation procedure.

ii. Additional Methods and Devices For Utilizing Ultrasound To preventOr Treat Vasospasm

As described above, the onboard ultrasound ablation component of theultrasound ablation/balloon dilation catheter device 10 may be utilizedin accordance with the vasospasm preventing/treating method of thepresent invention to prevent or treat the occurrence of vasospasm duringthe operative procedure. It will be appreciated, however, that theherein described method of preventing or treating vasospasm by deliveryof ultrasonic energy to the blood vessel may be accomplished by manyother types of devices and is not limited to the above-describedcombination ultrasound ablation/balloon dilation catheter device 10.Indeed, the present method of preventing or treating vasospasm bydelivery of ultrasound may be accomplished by passing an independent orseparate ultrasound transmission wire or waveguide through any workinglumen of an existing catheter, balloon dilation catheter, laser ablationcatheter, atherectomy catheter device or other intravascular catheter orsurgical member which has been inserted into the affected blood vessel.

Referring now to FIG. 7, there is shown a catheter device 114constructed in accordance with a second embodiment of the presentinvention. Catheter device 114 incorporates combined ultrasound ablationand laser ablation components, and generally comprises an elongatecatheter body 116 having a proximal end 118, a distal end 120, anddefining an outer surface 122 and an inner luminal surface 124. Mountedon the proximal end 118 of the catheter body 116 is a proximal endconnector assembly 126. As with the first embodiment, connected to theproximal end of the connector assembly 126 is an ultrasound transducer22. Additionally, an ultrasound generator 24 having a foot-actuatedon/off switch 26 is operatively connected to the ultrasound transducer22 so as to send ultrasonic energy through the catheter body 116 whendesired.

In the second embodiment, the catheter body 116 is formed from a singlelumen tube. Extending longitudinally through the catheter body 116 is anultrasound transmission member 128 having a proximal end which extendsthrough the connector assembly 126 and is interfaced to the ultrasoundtransducer 22 in the same manner previously described with respect tothe first embodiment. The ultrasound transmission member 128 furtherincludes an enlarged distal end 130 having a distal head 132 mountedthereon. Similar to the distal head 104 previously described withrespect to the first embodiment, the distal head 132 comprises agenerally round distal portion 134 and a reduced diameter neck orproximal portion 136. In the second embodiment, the outer diameter ofthe proximal portion 136 is approximately the same as or slightly lessthan the inner diameter of an annular recess 138 formed within the innerluminal surface 124 of the catheter body 116 adjacent the distal end 120thereof. In this respect, the proximal portion 136 of the distal head132 is inserted into the distal end 120 of the catheter body 116 to apoint where the distal most tip of the catheter body 116 abuts againstthe proximal aspect of the distal portion 134 of the distal head 132, asshown. As with the first embodiment, the distal head 132 may be retainedwithin the catheter body 116 via an adhesive or other suitableaffixation method. Additionally, formed within the proximal portion 136of the distal head 132 is a conical depression 140 which is used todirect a guidewire 142 of the catheter device 114 into the guidewirepassage aperture 144 formed within and extending longitudinally throughthe distal head 132. Like the guidewire passage aperture 110, theguidewire passage aperture 144 is sized so as to be slightly larger thanthe outer diameter of the guidewire 142 to be passed therethrough so asto permit fluid infused into the lumen of the catheter body 116 via anirrigation port 146 of the connector assembly 126 to be infused throughthe lumen and to pass out of the distal end 120 of the catheter body 116via the guidewire passage aperture 144, even when the guidewire 142extends therethrough.

In the second embodiment, the connector assembly 126 is formed in amanner substantially analogous to the connector assembly 20 previouslydescribed with respect to the first embodiment. In addition to theirrigation port 146, the connector assembly 126 also includes aguidewire insertion arm 148 as well as a diverter tube disposed thereinwhich is identically configured to the diverter tube 90 to cause theguidewire 142 to be directed through the guidewire insertion arm 148when such is extended longitudinally through the lumen of the catheterbody 116.

Though being substantially identical to the connector assembly 20, theconnector assembly 126 of the second embodiment includes, as analternative to the balloon inflation port 78, a laser energytransmitting member introduction port 150 which is included inapproximately the same position as the previously-described ballooninflation port 78. In the second embodiment, introduction port 150includes a hollow bore extending therethrough which is in communicationwith the longitudinal bore of the connector assembly 126 as well as thelumen of the catheter body 116. Disposed within and extendinglongitudinally through the lumen of the catheter body 116 are aplurality of laser energy transmitting members 152 which are insertedinto the lumen of the catheter body 116 via the introduction port 150.The laser energy transmitting members 152 each include proximal endsWhich are connected to a laser energy transmission source 154 ofsufficient energy and absorption characteristics to ablate plaque orother obstructing material such as thrombus. For example, a visiblewavelength laser which is highly absorbed by blood components or anear-infrared laser that is highly absorbed by the water component ofthe obstructing tissue or matter, may be used. The distal ends of thetransmitting members 152 extend through the distal head 132 and aresubstantially flush with the distal aspect of the distal portion 134thereof. Alternatively, the transmitting member 152 may be distallyabutted against a transparent lens cap or window member capable oftransmitting or allowing passage therethrough of a preselectedwavelength (e.g. a quartz or sapphire lens). Though, as shown in FIGS.7-10, six laser energy transmitting members 152 are incorporated intothe catheter device 114, it will be recognized that greater or fewernumbers of transmitting members 152 may be used. In the secondembodiment, the transmitting members 152 comprise optical fibers, thoughit will be recognized that as an alternative to such optical fibers,other laser energy transmission means, such as a suitable liquid, may beutilized as an alternative. In this respect, if a liquid laser energytransfer medium is utilized, the transmitting members 152 will not beincluded in the catheter device 114.

In utilizing the catheter device 114 of the second embodiment, theguidewire 142 is initially inserted into the lumen of the blood vessel,with the catheter body 116 being subsequently advanced thereover. Oncethe distal end 120 of the catheter body 116 is positioned within theblood vessel adjacent the occlusive lesion, the laser energytransmission source 154 is activated thus facilitating the transmissionof laser energy out of the distal en 120 via the laser energytransmitting members 152. In the event the exposure of the occludedregion of the blood vessel to the laser energy causes a vasospasm tooccur, the laser energy transmission source 154 is deactivated, and theultrasound transducer 22 activated. The activation of the ultrasoundtransducer 22 oauses ultrasonic energy to be transmitted from the distalend 120 of the catheter body 116 via the ultrasound transmission member128.

Referring now to FIGS. 11 and 12, as will be recognized, the ultrasoundtransmission member may be utilized to relax a vasospasm irrespective ofwhether such is incorporated into a catheter device including balloondilation, laser ablation or atherectomy ablation components. In thisrespect, an ultrasound transmission member 300 operatively connected toan ultrasound transducer 22 and corresponding ultrasound generator 24 inthe same manner previously discussed with respect to the aforementionedthree embodiments of the present invention may be inserted into anyconventional connector assembly 302 of a catheter device for purposes ofeliminating vasospasm. In this respect, when the catheter body of thecatheter device is advanced over the guidewire 304, and a vasospasmoccurs as a result of any procedure being conducted within the bloodvessel, the guidewire 304 may be removed from within the lumen of thecatheter body and replaced with the ultrasound transmission member 300.Thereafter, the ultrasound generator 24 may be activated thereby causingthe ultrasound transducer 22 to transmit ultrasonic energy to the distalend of the catheter body via the ultrasound transmission member 300, soas to alleviate the vasospasm. Additionally, the ultrasound transmissionmember 300 may also be inserted through the lumen of the catheter bodywithout removing the guidewire from there within. As such, for thismanner of operation, all that is required is that the connector assembly302 be adapted to accommodate both the guidewire 304 and ultrasoundtransmission member 300.

The method of preventing or treating vasospasm in accordance with thepresent invention may also be utilized in conjunction with anyatherectomy catheter or other device for cutting, shaving, grindingand/or aspirating occlusive matter from the lumen of the blood vessel.To effect the delivery of vasorelaxant ultrasound energy in accordancewith the invention, an ultrasound transmission member may be passedthrough or positioned within the elongate body of an atherectomycatheter.

Examples of atherectomy catheters Wherein an ultrasound transmissionmember 200 may be permanently positioned, or temporarily inserted, toeffect vasorelaxation in accordance with the present invention, includethose devices described in U.S. Pat. No. 4,765,332 (Fischel) entitledPULLBACK ATHERECTOMY CATHETER SYSTEM, PCT INTERNATIONAL PATENTPUBLICATION NO. W0 89/05611 (Muller) entitled ATHERECTOMY DEVICE WITHANGIOPLASTY BALOON AND METHOD, EUROPEAN PATENT PUBLICATION NO. 347,098A2(Shiber) entitled ATHERECTOMY SYSTEM WITH A GUIDEWIRE, U.S. Pat. No.5,100,423 (Fearnot) entitled ABLATION CATHETER and U.S. Pat. No.4,924,863 (Sterzer) entitled ANGIOPLASTIC METHOD FOR REMOVING PLAQUEFROM A VAS.

In accordance with the invention, FIGS. 13 and 14 show an atherectomycatheter device 200 comprising an elongate catheter body 202 having aproximal end, a distal end and a lumen 204 extending therethrough. Adrive member or shaft 206 extends longitudinally through lumen 204. Acutting or grinding apparatus 208 is mounted on the distal end ofdriveshaft or member 206. The driveshaft or member 206 is then utilizedto operatively manipulate (e.g. rotate and/or longitudinally back and/orforth) the cutting apparatus 208 so as to remove or cut occlusive matterfrom the blood vessel lumen, immediately ahead of the distal end of thecatheter body 202. A power drive unit 210 may be connected to theproximal end of the driveshaft or member 206 to rotate, longitudinallymove, or otherfwise drive or energize the driveshaft or member 206 in amanner that will effect the desired cutting movement of the cuttingapparatus 208.

A proximal end connection apparatus 212 is formed on the proximal end ofthe catheter body 202 and incorporates an elongate hollow inner borewhich is fluidly consistent with lumen 204 of catheter body 202. Asuction/infusion sidearm 214 is formed on the proximal end connectorapparatus 212 to permit infusion of fluid in a proximal directionthrough lumen 204 of catheter body 202 and/or to permit aspiration orwithdrawal of fluid, debris or excised occlusive material in a distaldirection through the lumen 204 of catheter body 202.

The ultrasound transmission member 128a is connected at its proximal endto ultrasound transducer 22. The ultrasound transducer 22 is connectedto the signal generation unit 24. The signal generation unit 24 isactuatable by way of foot pedal 26. A signal generation unit 24 andultrasound transducer 22 are operative to generate ultrasonic energywithin the frequency range of 1-1000 Khz and preferrably approximately20 Khz. Thus, when actuated, ultrasonic energy within the range of1-1000 Khz and preferrably approximately 20 Khz will pass through theultrasound transmission member 128a to the distal end thereof. Thedistal end of ultrasound transmission member 128a is affixed to the bodyof the catheter 202 near the distal end thereof so as to causeultrasonic end vibation of the distal end of the catheter body 202.

In accordance with the invention, if vasospasm is encountered prior to,during or immediately after the atherectomy procedure, the signalgenerator 24 and ultrasound transducer 22 may be utilized to sendvasorelaxant ultrasound energy through the ultrasound transmissionmember 128a, causing the distal portion of the catheter body 202 toundergo ultrasonic vibration within the frequency range of 1-1000 Khzand preferrably approximately 20 Khz. Such ultrasonic vibration of thecatheter body will result in vasorelaxation or reversal of the vasospasmin the region of blood vessel immediately adjacent the vibrating portionof the catheter body 202. In some embodiments of the invention whereinthe driveshaft or member 206 is longitudinally extractable, the cuttingapparatus 208 may be extracted into the distal end of the lumen 204prior to initiation of the ultrasonic vasorelaxant treatment.

Also, in accordance with the invention, the catheter body 202 may begently moved back and forth to effect the desired ultrasonicvasorelaxant treatment over an extended length of blood vessel whereinthe vasospasm is present.

In each of the aforementioned embodiments of the present invention, thecatheter bodies 12, 116 may comprise multilumen tubes having at leastfirst and second lumens extending longitudinally therethrough whereinone such lumen is used to accommodate the respective ultrasoundtransmission member with the second lumen being used as a ballooninflation lumen, laser energy transmitting member passage lumen, ordrive member passage lumen.

Although the invention has been described herein with specific referenceto presently preferred embodiments thereof, it will be appreciated bythose skilled in the art that various additions, modifications,deletions and alterations may be made to such preferred embodimentswithout departing from the spirit and scope of the invention.Accordingly, it is intended that all reasonably foreseeable additions,deletions, alterations and modifications be included within the scope ofthe invention as defined in the following claims.

What is claimed is:
 1. A method of treating vasospasm during atransluminal balloon angioplasty procedure wherein a catheter having adilation balloon formed thereon, and at least one lumen extendinglongitudinally therethrough, has been inserted into the blood vessel,and wherein vasospasm has occurred adjacent the distal end of saidcatheter, said method comprising the steps of:a) inserting an elongateultrasound transmission member through the lumen of said catheter; b)connecting said elongate ultrasound transmission member to an ultrasoundgenerating system operative to generate ultrasound energy within thefrequency range of 10-1000 kHz; and, c) passing ultrasonic energy withinthe frequency range of 10-1000 kHz through said ultrasound transmittingmember to effect treatment of said vasospasm adjacent the distal end ofsaid catheter body.
 2. The method of claim 1 wherein step (c)specifically comprises:passing ultrasound having a frequency ofapproximately 20 Khz through said ultrasound transmission member toeffect ultrasonic treatment of the vasospasm adjacent the distal end ofsaid catheter body.
 3. The method of claim 1 further comprising:(d)moving said catheter body back and forth to increase the size of theregion of blood vessel to which ultrasonic treatment is delivered. 4.The method of claim 1 further comprising:(d) moving the ultrasoundtransmission member back and forth to increase the size of the region ofblood vessel to which ultrasonic treatment is delivered.